There's an excellent overview of the dodgy ingredients that are used by the food industry as flavour enhancers and "glutamate containing ingredients" in Today Tonight's recent Natural Additives story http://www.todaytonightadelaide.com.au/, plus advice on the one natural colour that is as bad as artificial colours for many children.

See also blog from Sue Dengate http://au.news.yahoo.com/today-tonight/blogs/article/-/14016919/understanding-natural-additives/